You are not supposed to treat it as a gospel, following every guideline. Instead, it is a collection of ideas presented to you, so that you can decide if you want to use them (or not!) in your day-to-day work.

In general, software development is not a profession where you learn how to do things and do them, occasionally refreshing your skills. It is a perpetual problem solving field (not without its routines), and a continuous journey. Creativity, personal opinions and exchange of ideas play an integral role in this profession.